AFAIK there are no aimbots so far that are effective enough to be of any use. Also unlike other games projectile travel time is slow af, making strafing and dodging easy as hell, an aimbot is more of a detriment unless it knows how to lead shots.
Good aim is being able to turn 180° pull off a few consecutive headshots on new players and then continuing on your way. Like I said this mod is ancient, so "good" here is not like "good" in the newest COD game its' more akin to having 4000 hours over 10 years and being able to snipe people with your eyes closed. You can still find oldfags running around dotf classic from time to time with the alias "Padawan" ranking at the top of the scoreboard, it's nothing to do with cheats, they really are that good. Try playing old Quake Multiplayer games and seeing how good people are in those.
No doubt this happens, and while I like to troll the devs they are very strict about any of this kinda stuff, which I appreciate. I remember us simply having nightshades in our clan, not even distributing or using his PB/SB/Wall Hacks, had us delisted and ostracised by the development team until we threw him under the bus like the (((People))) we are. I have no doubt in secret chats on the Je'daii discord Kronos still distributes his SB hacks and there's a bunch of retards who use them but generally, the few who do, get caught out quickly and you'll see they are banned on every major clan, official and large private-run servers. There's probably a few that slip through the cracks but they're exception not the rule.
I recommend picking servers with white names if you're relatively new, or joining a clan. That way you can either play against people of similar skill level to you and thus improve yourself until you're able to compete with the oldfags or joining a clan (even if only to learn and ditching them immediately after) where one of the more veteran players can teach you/help you master all the tricks, skills and gimmicks of gameplay.
I don't think most people would, it takes the fun out of the game for anyone but griefers, like I said there is no doubt a few cheaters who run under the radar and you can find occasionally on major servers but they are very rare.